The objective of this work was to evaluate the effects of γ irradiation (0, 2, 4 and 6 kGy doses), applied on frozen and packaged headed shrimps, on pathogenic Vibrio cholerae O1 and Salmonella enteritidis bacteria, as well as on some of the physical and sensory characteristics of this kind of food. The 6 kGy dose was highly efficient in inhibiting V. cholerae O1 and S. enteritidis and in decreasing lipid oxidation in shrimps compared with the nonirradiated product. Shrimp texture was not affected by any of the irradiation doses studied, but the lightness of the surface color increased in shrimps irradiated with 6 kGy compared with those irradiated with 2 kGy. Shrimps irradiated with 6 kGy showed lower overall acceptability than those irradiated with 2 kGy or were nonirradiated. The application of γ irradiation in doses up to 6 kGy on frozen and packaged headed shrimps could improve the microbiological quality of this commodity. PRACTICAL APPLICATIONS The use of γ irradiation has the potential to ensure safety effectively by inactivating bacteria, increasing shelf life and maintaining food quality without significant chemical changes in the food matrix. Besides, this process can be applied to frozen and packaged products. Thus, irradiation of frozen and packaged shrimps could benefit the local processing industry, which could offer the international market a high‐quality product, with an additional safety treatment.

FRUIT. Effects of two ethylene inhibitors, 1-methylcylopropene (1-MCP) and aminoethoxyvinylglycine (AVG), on production of volatile compounds and mangiferin (a bioactive xanthone) in 'Tommy Atkins' mango fruit were investigated. Volatile composition and mangiferin content, in treated and untreated fruits at three maturity, stages were determined by SPME-GC-MS and HPLC, respectively. These chromatographical analysis revealed that the volatile profiles and mangiferin concentrations were not significantly different, suggesting that the use of ethylene inhibitors does not affect the mango aroma and functional properties relative to this xanthone. Moreover, a simple, precise and accurate HPLC method was developed for quantifying mangiferin in mango pulp.Keywords: Mangifera indica; ethylene inhibitors; mangiferin. INTRODUÇÃOInibidores de etileno são agentes químicos capazes de inibir ou retardar os efeitos do etileno, um fito-hormônio ubíquo nos vegetais superiores e responsável por regular várias respostas fisiológicas. 1Em virtude do papel importante do etileno na indução do amadurecimento de frutos climatéricos, inibidores de etileno tais como 1-metil-ciclopropeno (1-MCP) e aminoetoxi-vinil-glicina (AVG) têm sido empregados com sucesso na conservação pós-colheita de frutas e hortaliças. 1,2Em frutas como maçã, abacate, pera e manga, o efeito dos inibidores de etileno no retardo do amadurecimento pode ser facilmente evidenciado pelo atraso na mudança de coloração da casca/polpa e pela maior firmeza da polpa em relação a frutos não tratados. O efeito observado depende do tipo de inibidor utilizado (dose, nº de aplicações, duração e temperatura do tratamento) e da fruta tratada (cultivar e estádio de maturação na colheita). 2,3O uso de inibidores de etileno propicia um incremento na vida útil de frutas, que pode viabilizar a comercialização para mercados mais distantes dos países produtores. Entretanto, aplicações de inibidores de etileno podem promover efeitos indesejáveis que geram dúvidas quanto aos seus benefícios, como alterações no aroma da fruta, e efeitos deletérios sobre a presença de compostos de importância nutricional, 2 repercutindo negativamente na aceitabilidade da fruta pelo consumidor e, consequentemente, no valor de mercado do produto. 4 AVG e 1-MCP afetaram a produção total de compostos voláteis (terpenos, cetonas, aldeídos, ésteres e alcoóis de baixo peso molecular) em banana, maçã, pera, melão e manga, sendo que alguns deles são componentes odoríferos característicos do aroma e do sabor destas frutas.5-10 Em morango, pera, abacaxi e manga, inibidores de etileno também afetaram os teores de substâncias bioativas (ex.: vitamina C e flavonoides), 2,11,12 as quais são hoje amplamente valorizadas pela população devido às suas propriedades benéficas à saúde. 4 Em manga 'Tommy Atkins' (variedade mais cultivada no Brasil), 13 a aplicação de inibidores de etileno prolongou em alguns dias a vida útil dos frutos, através do retardo no amaciamento e na mudança da coloração da polpa, bem como pela limitação da...

Strawberry is considered a fruit of great commercial interest in many countries due to its color, aroma, flavor, and nutritional properties. However, it is possible that the differences among the cultivation systems could affect the production of photoassimilates in the plant and, consequently, their partitioning into the fruits composition, influencing its quality. Therefore, the aim of this work was to evaluate the influence of the cultivation systems (hydroponics in gutters and slabs, and conventional) and genotype on the physicochemical properties, antioxidant and sensory activity in strawberry fruits. The experiment was carried out using a completely randomized design in a factorial 4 × 3 scheme with four replications, represented by trays of approximately 200 g of fruit. In the Laboratory, the strawberries (cv. Oso Grande, Festival, Camarosa, and Albion) were analyzed for their physicochemical properties and sensory variables: titratable acidity (TA), soluble solids (SS), SS/TA ratio, soluble sugars, vitamin C, polyphenol, and antioxidant activity. It was observed that cultivation systems and genotype studied influence the antioxidant activity, physicochemical and sensory properties of strawberries. The conventional system shows higher values for physicochemical variables and antioxidant activity, with cultivar variation within each system. The antioxidant activity attributed to strawberry is strongly related to the content of extractable polyphenols and vitamin C. Regarding the sensory properties, cultivars show good overall acceptability in all production systems studied, no presenting difference among systems.

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